Deadly
Species with venom, bite force, or hunting ability sufficient to kill a person. Most want nothing to do with us, which is the only reason the numbers stay low.
Reticulated Python
The longest python, up to 33 feet of snake with black X's running down its back in a diamond-like pattern.
Russell's Viper
A South Asian viper whose venom varies across India, enough that one antivenom did poorly against snakes from the semi-arid north in mouse tests.
Shortfin Mako Shark
Considered the fastest shark in the world: burst speeds up to 70 km/h, warm swimming muscle, and hook-like, razor-edged teeth.
Sloth Bear
Missing top front teeth, a vacuum-cleaner mouth for termites, and a stand-and-fight defense against tigers.
South American Bushmaster
The longest of all vipers, able to aim a strike in the dark by body heat alone, from the only pit vipers in the Americas that lay eggs.
Southern Black Widow
Shiny black spider whose venom floods the nerve-muscle junction with acetylcholine and noradrenaline.
Southern Cassowary
A five-inch dagger-like claw on each foot, a leap of up to seven feet, and a casque that glows under ultraviolet light.
Spotted Hyena
Bone-crushing jaws, matriarchal clan rule, and a whoop that carries for miles.
Sydney Funnel-Web Spider
Male venom carries a nerve toxin that likely evolved to deter bandicoots and birds, and is lethal to humans by unfortunate coincidence.
Tiger Shark
A shark with a reputation for eating almost anything, serrated teeth that can pierce sea turtle shells, and a habit of hunting at night.
Timber Rattlesnake
The big eastern pit viper that senses heat, waits in ambush and rattles a warning first.
Tsetse Fly
A blood-drinking fly that makes milk and gives birth to a larva nearly as big as she is.
Volta Electric Eel
The biological super-battery that hit 860 volts, the strongest electric discharge known from any living animal.
Western Diamondback Rattlesnake
A desert pit viper with a heat-sensing pit on each side of its head. In one study, fasting snakes lost 30% of their body mass over 168 days.
Wild Boar
A long-snouted omnivore whose upper canines are usually visible even when its mouth is closed.
Yellow Fever Mosquito
A mosquito about a quarter of an inch long whose yellow fever cost U.S. troops more casualties than enemy fire in the Spanish-American War.